Electromagnetic type hair clipper



C59 DHETZES E.LQE

Gehe .RIZ-Eff C. B. LEE ET AL ELECTROMAGNETIC TYPE HAIR CLIPPER Jan. 11,1955 Filed Feb. 15, 1951 Jan. ll, 1955 c. a. LEE Erm.

ELECTROMAGNETIC TYPE HAIR CLIPPER Y 2 Sheets-Sheet 2 Filed Feb. l5 1951Jndwma/ 5215112515 E. le@

Een; MNE/"f United States Patent O ELECTROMAGNETIC TYPE HAH! CLIPPERCharles B. Lee and Gene M. Nelf, Racine, Wis., assignors to John OsterManufacturing Company, Racine, Wis., a corporation of WisconsinApplication February 15, 1951, Serial No. 211,066

11 Claims. (Cl. 310-29) This invention relates to electromagneticallypowered hairclippers wherein the movable blade is reciprocated by anarmature which is intermittently drawn toward the pole of an alternatingcurrent electromagnet against the tension of a spring incorporated inthe mounting of the armature, the periodicity of the resulting vibrationof the armature being governed by the frequency of the alternatingcurrent used to energize the electromagnet; and has as its purpose toprovide an improved clipper of this type.

With a view toward facilitating assembly of the c1ipper duringmanufacture this invention provides an irnproved manner of mounting thearmature so that its assembly with the rest of the structure isaccomplished by merely dropping the armature down into the lower half ofthe sectional housing or case in which the instrumentalities of theclipper are assembled and which also serves as a handle for the clipper.

Another object of this invention is to provide an improved resilientmounting for the armature which is so designed and constructed that allparts thereof, with the exception of that portion thereof which providesthe spring proper, are reinforced against dellection or exure of anykind, and so that a single relatively stit leaf spring provides theentire spring action, an advantage of this construction being that bythe simple eX- pedient of reducing the thickness of the leaf spring itis possible to adapt the clipper to operation with voltages of differentfrequencies.

A still further object of this invention is to provide an improvedmanner of mounting the electric switch for the clipper whereby thesecurement of the complementary housing sections of itself fixes theswitch in position in a manner whereby the opening through which theswitch actuator protrudes is tightly closed to assure against theingress of hair into the body or housing of the clipper.

With the above and other objects in view, which will appear as thedescription proceeds, this invention resides in the novel construction,combination and arrangement of parts substantially as hereinafterdescribed and more particularly defined by the appended claims, it beingunderstood that such changes in the precise embodiment of thehereindisclosed invention may be made as come Within the scope of theclaims.

The accompanying drawings illustrate one complete example of thephysical embodiments of the invention constructed according to the bestmode so far devised for the practical application of the principlesthereof, and in which:

Figure 1 is a side elevational view of a clipper embodying thisinvention, parts thereof being broken away and in section;

Figure 2 is a top plan view of the clipper with the upper half of itshousing or case removed;

Figure 3 is a cross sectional view through the clipper on the plane ofthe line 3-3 in Figure 2;

Figure 4 is a cross sectional view through the clipper on the plane ofthe line 4--4 in Figure 2;

Figure 5 is a fragmentary detail sectional view through the switch andadjacent portion of the clipper, said view being taken on the plane ofthe line 5-5 in Figure 2;

Figure 6 is an exploded perspective view of the main portions of theclipper and showing the armature removed from but in position to bedropped down into the lower half of the clipper housing or case;

2,699,509 Patented Jan. 1l, 1955 Figure 7 is a detail sectional viewthrough the movable blade and the adjacent portion of the connectionbetween it and the armature;

Figure 8 is a detail perspective view of the mounted end of the armatureand illustrating particularly the bracket-like stamping which providesthe resilient mounting for the armature;

Figure 9 is a fragmentary perspective view showing a detail in theconstruction of the cover section of the housing or case; and

Figure 10 is a detail sectional view through Figure 4 on the plane ofthe line 10-10.

Referring now particularly to the accompanying drawings in which likenumerals indicate like parts throughout the several views, the numeral 9indicates generally the sectional housing or case of a hair clipperembodying this invention and which in the present instance comprises alower body section 10 and an upper cover section 11. The drivinginstrumentalities of the clipper indicated generally by the numeral 12are contained entirely with the housing or case, which as is customaryis of a size to be conveniently held in one hand. They are assembledupon the interior of the body section 10. Hence the assembly can becompleted before the cover section 11 is secured in position, which isdone by means of fastening screws (not shown) passing through holes inthe cover and threaded in tapped sockets 13 in the body section.

The clipper includes the customary cooperating stationary and movableshearing blades 14-15, the former being secured by screws 16 to theinclined front wall 17 of the body section and the latter being carriedby an armature indicated generally by the numeral 18. The holes in thestationary blade 14 through which its fastening screws 16 pass arepurposely made somewhat larger than the shank of the screws to enableslight lateral adjustment of the stationary blade in the securementthereof.

The movable blade 15 is connected to the armature 18 by a drivingconnection 19 to be hereinafter more fully described, which not onlyconnects the blade 15 with the armature so that it moves therewith, butalso applies a downward spring tension on the movable blade to press thesame firmly against the stationary blade, the spring tension by whichthis engagement is maintained being adjusted by means of a set screw 20equipped with the customary lock nut.

The armature 18 is composed of a stack of substantially L-shapedlaminations each of which has a base or foot portion 21 and a stern orleg portion 22. The blade driving connection 19 is secured to the baseor foot portion by rivets 23 which, of course, also hold the armaturelaminations together at this point. The portion 21 is thus the free endof the armature and at its opposite or mounted end the laminations ofthe armature are clamped together by being embraced between the arms 24of a U-shaped metal stamping indicated generally by the numeral 25 andwhich, as will be hereinafter more fully described, constitutes an eS-sental part of the spring mounting of the armature.

It is to be observed that the arms 24 of the U-shaped stamping 25 areelongated toward the free end of the armature to provide attaching ears26 which are the actual portions of the arms 24 embracing the sides ofthe armature. Rivets 27 pass through these attaching ears and thearmature to fasten the stamping 25 to the armature and also rmly clampits laminations together.

Attention is directed to the fact that the bight 28 of the U-shapedstamping is spaced from the plane of the adjacent inner face 29 of thearmature and that a tongue-like extension 30 projects inwardly from thebight to overle and be spaced from this portion of the armature. Thetongue-like extension 30 provides a relatively stii leaf spring so thatby anchoring the outer end portion of this spring the armature isresiliently mounted in a manner enabling it to be vibrated toreciprocate the movable shearing blade. An electromagnet indicatedgenerally by the numeral 31 provides the means for vibrating thearmature, it being understood that upon energization of theelectromagnet with an alternating current the armature is periodicallyor intermittently attracted toward the poles of the electromagnetagainst the tension of the relatively stiff leaf spring 30.

The manner in which the tongue or leaf spring 30 and consequently thearmature is mounted is an important feature of this invention but beforedescribing the same it should be noted that the electromagnet 31 whichconsists of a substantially E-shaped laminated core 32 and a coil orwinding 33 mounted upon the center leg 34 of the core is fixed in thebottom of the body between the medial portion thereof and the front endof the clipper. The three legs of the core 32, of course, provide thepoles of the electromagnet and as best seen in Figure 2 the outer leg35, which is farthest from the front end of the clipper, and the centerleg 34 are of the same length and have their pole faces lying insubstantially a common plane facing the adjacent side wall of theclipper housing. The space between this side wall of the housing andthese pole faces accommodates the leg 22 of the armature. The innersurface of the leg 22 thus overlies and coacts with the pole facesprovided by the legs 34 and 35 of the magnet core.

The other leg 36 of the magnet core which is nearest the front end ofthe clipper is shorter than the legs 34 and 35 and in fact extends forless than half of the height of the coil, but the combined length ofthis short leg and the length of the base portion 21 is such that whenthe stem portion 22 of the armature engages the pole faces of the longlegs the base portion also just contacts the pole face of the short leg36. No part of the armature extends forwardly of the core of theelectromagnet.

The mounting for the armature is so designed that the armature, with theU-shaped stamping 25 secured thereto, is assembled with the rest of themechanism by merely dropping the armature down into the body 10. To thisend a clamping screw 37 passes through a hole 38 in the outer endportion of the tongue-like extension 30 and through a clamping plate 39and is threaded in a nut 40. These parts are so proportioned that uponassembly of the armature with the body 10 the screw 37 drops down intoan open topped slot 41 in a boss 42 extending up from the bottom of thehousing and disposed between the electromagnet and the rear end of theclipper.

With the parts so positioned the screw 37 which is preferably of theAllen-head type may be tightened to draw the tongue 30 against theadjacent flat face 43 of the boss, and since that side of the bossfacing the tongue 30 is relieved as at 44 it is evident that the tongue30 may iiex to allow swinging or vibratory motion of the armature 18. Itwill also be understood that since the arms of the U- shaped stampingare disposed edgewise to the direction of armature movement they willnot yield or in anywise defleet. All iiexure involved is thus localizedin the spring blade provided by the tongue 30 and more particularly thatportion thereof lying between the arms of the stamping and the area atwhich the tongue is clamped to the side of the boss.

Since the U-shaped stamping should be absolutely secure against anypossible deflection resulting from the movement of the armature it ispreferable that the arms thereof be reinforced against deflection and tothis end they are extended in width as at 45 and have longitudinal lyextending parallel beads 46 formed therein. As best seen in Figure 8these beads also serve as abutments against which the adjacent edges ofthe armature engage to thereby locate the parts with respect to eachother and assure against any possible displacement of the stamping withrespect to the armature.

It is, of course, important that the normal periodicity of the leafspring provided by the tongue 30 be properly related to the frequency ofthe energizing voltage. Ordinarily the stamping is so designed that theleaf spring 30 is correct for 60 cycle alternating current voltage. Toadapt the same to a lesser frequency as, for instance, the 50 cyclecurrent found in most European countries, it is only necessary to grindoff a little of the outer face of the leaf spring to reduce itsthickness proportionately. By virtue of the novel design andconstruction of the stamping 25 this is readily possible and does notinvolve costly design changes or the stocking of different kinds ofparts to tit the varying needs of the manufacturer.

Though the spring blade provided by the tongue 30 affords sufficientspring tension under normal circumstances, to enable adjustment of thedriving unit to different voltages, an auxiliary coiled compressionspring 47 is provided. This spring is confined between the head of anadjusting screw 48 and the bight 28 of the U-shaped stamping, and thescrew passes through a hole 49 in the stamping and is threaded in a nut50 which during assembly is dropped into an appropriately shaped cavity51 in the boss 42. Ordinarily the tension of the spring 47 is soadjusted at the factory that the clipper operates properly at 60 cyclecurrent of 110 volts, the adjustment being such that the armature justclears the pole faces of the electromagnet at this voltage.

If the voltage where the clipper is placed in service consistently runsan appreciable amount above 1l() volts, as for instance l2() volts, thecombined tension of the spring 47 and the blade 30 would not be suicientto keep the armature from striking the pole faces. Likewise if thevoltage at the place of use consistently runs an appreciable amount lessthan volts, as for instance 100 or 105 volts, the magnet would not havesuicient strength to provide the proper throw of the armature and themovable blade carried thereby. These conditions can be satisfactorilymet by the simple expedient of adjusting the screw 48 to increase ordecrease the spring tension.

Since tightening or loosening of the screw 48 affects the normal restposition of the free end of the armature and consequently the movableblade carried thereby, whenever such adjustment is made the position ofthe stationary blade should be correspondingly reset, and to do somerely requires loosening the fastening screws 16, shifting thestationary blade the slight amount required, and retightening thefastening screws. In this manner the proper positional relationship isat all times assured between the cooperating blades.

The driving connection 19 between the movable blade and the free end ofthe armature consists of an appropriately shaped spring arm 52 anchoredto the underside of the armature by the rivets 23 and an overlying stiffarm 53 anchored to the top side of the armature by the rivets 23, theset screw 20 being threaded in the stiff arm 53 and bearing against thespring arm 52. The outer end of the spring arm is bifurcated to providetwo spring iingers 54 and each of these has a short cylindrical pin 55projecting from the underside thereof to be received in one of a pair ofholes 56 in the movable blade. The center-tocenter distance between thepins 55 (designated S in Figure 7) is slightly less than thecenter-to-center distance between the holes 56 (designated L in Figure7). Thus upon engagement of the pins in the holes the spring lingers aresprung slightly apart to thereby assure a rm driving connectionregardless of wear.

Another feature of this invention concerns the manner in which theswitch 57 (which controls operation of the clipper) is mounted. As willappear the arrangement is such that the front wall 58 of the switch fromwhich the switch actuator 59 projects is tightly pressed against theinside of the housing wall all around the opening 60 therein throughwhich the switch actuator protrudes and the switch held in place by thesimple expedient of drawing the housing sections together. To this endthe body 10 of the housing is formed with a shelf 61 from which thehousing side wall 62 rises, and the cover 11 has an inwardly directedledge 63 from which its side wall 64 extends, the side wall 64 havingthe opening 60 therein. The inner faces of the side walls 62 and 64 arecoplanar except to the extent the slight inclination of these wallsurfaces resulting from the draft necessary for molding the housingsections disposes them at a broad obtuse angle.

These inner faces of the side walls 62 and 64 together are of a size tocover the entire front wall 58 of the switch body, and to press this atface of the switch body against the walls 62 and 64 as the housingsections are drawn together the boss 42 has two vertical ribs 65 spacedfrom the inner faces of the walls 62 and 64 a distance slightly lessthan the depth of the switch. The crowns of these ribs 65 are alsoinclined slightly as indicated by the dimension A in Figure 4, whichangularity is the result of draft requirements. Hence, it follows thatas the housing sections are drawn together the switch is clamped orpinched between the ribs 65 and the opposing inner surfaces of the walls62 and 64. A cushion pad of felt or similar material 66 preferablyoverlies the ledge 63 in the cover to compensate for the slightvariations in dimensions encountered in production. Clearance isafforded for the electrical terminals 67 of the switch and theconductors leading therefrom by a cavity 68 having an inclined side wallas best seen in Figure and to hold the switch against endwise shiftingthe cover has two small pins 69 and 70 depending from the ledge 63 toengage the endsY of the switch as shown in Figure 10.

From the foregoing description taken in connection with the accompanyingdrawings and the following claims, it will be readily apparent to thoseskilled in the art that this invention provides a greatly improved'hairclipper of the electromagnetically driven type.

What we claim as our invention is:

l. A vibratory motor comprising: an electromagnet having a pole; a rigidarmature; a U-shaped metal stamping straddling one end portion of thearmature; means rigidly securing the arms of the stamping to thearmature; a flat tongue-like extension on the bight of the U-shapedstamping providing a relatively stiff leaf spring overlying and spacedfrom the adjacent portion of the armature; the arms of the U-shapedstamping being rigid against llexure in all directions; and meansanchoring the free end portion of the leaf spring in fixed relation tothe electromagnet and with the armature overlying the pole of theelectromagnet and movable toward and from said pole as said leaf springllexes.

2. A vibratory motor comprising: an electromagnet having a pole; a rigidarmature; and means mounting the armature for vibratory motion towardand from said pole of the electromagnet comprising a U-shaped metalstamping having its arms snugly embracing and fixed to one end portionof the armature, a flexible tonguelike extension on the bight of theU-shaped stamping atwise overlying and spaced from the adjacent portionof the armature, and means rigidly anchoring the free end portion ofsaid tongue-like extension in fixed relation to the electromagnet withthe plane of the tonguelike extension normal to the direction ofvibratory motion of the armature, said U-shaped stamping being rigidagainst deformation except for atwise flexure of its tongue-likeextension so that the flexure necessary to permit vibratory motion ofthe armature is localized in the flat tongue-like extension.

3. A vibratory motor comprising: a stationary magnet coil having a polepiece; an elongated armature having one end portion overlying andmovable toward and from said pole piece; an elongated housing section inwhich the stationary magnet coil is mounted, said housing section havingan upstanding boss between one end thereof and the stationary magnetcoil, said boss having a slot opening to its top with the sides of theslot substantially parallel with the axis of the coil; a U- shaped metalstamping embracing and fixed to the other end portion of the armature,the bight of the U- shaped stamping being extended toward the firstdesignated end of the armature to provide a relatively stiff leaf springoverlying and spaced from the adjacent portion of the armature; and aheaded clamping screw passing through a hole in the leaf spring near itsouter end, said screw lying in the bottom of said slot in the boss, andhaving a nut threaded thereon so that the outer end portion of the leafspring may be removably clamped to one side of the boss to resilientlymount the armature thereon with its medial portion extending across themagnet coil.

4,. In a vibratory motor: an elongated laminated armature; anelectromagnet for attracting the armature; and means resilientlymounting the armature at one end portion for lateral vibratory motion,comprising a U- shaped metal stamping embracing said end portion of thearmature with the arms of the U-shaped stamping atwise engaging itsouter laminations, means securing the arms of the stamping to thearmature, the bight of the U-shaped stamping being extended toward theopposite end of the armature to provide a relatively stiff leaf springflatwise overlying and spaced from the adjacent portion of the armatureand disposed substantially normal to the edges of the armaturelaminations, and meansrigidly anchoring the outer end portion of theleaf spring in fixed relation to said electromagnet.

5. In an electromagnetic vibration motor: an elongated housing section;an electromagnet coil mounted in said housing section and provided withpole faces facing one side of the housing section; an upstanding boss onthe housing section between the magnet coil and one end of the housingsection, said boss having a ilat face substantially parallel with thepole faces of the electromagnet; a

rigid armature of a length to extend across the pole faces of the magnetcoil and past said boss; and a spring mounting for one end of thearmature and by which the armature is supported for lateral movementtoward and from the pole faces of the magnet coil, said spring mountingcomprising a U-shaped metal stamping having its arms embracing andrigidly secured to the armature, the bight of the U-shaped stampingbeing extended to provide a relatively stiff leaf spring overlying andspaced from the adjacentvportion of the armature; and means for clampingthe outer end portion of said leaf spring to said face of the boss sothat all fiexure of the armature mounting necessary for movement of thearmature toward and from the pole pieces is localized in that portion ofthe leaf spring lying between its anchored end portion and the bight ofthe U-shaped stamping.

6. In a vibratory magnetic device: a movable armature comprising a stackof laminations rigidly secured together; and a springmounting for saidarmature comprising a U-shaped metal stamping having its arms overlyingand fixed to the outer laminations of the armature at one end portionthereof to rigidly secure the stamping to the armature; the bight of theU-shaped stamping having a llat tongue-like extension forming arelatively stiff leaf spring overlying and spaced from the adjacentedges of the armature laminations; all portions of the stamping beingstiff to resist deflection except said extension which provides the leafspring so that by firmly anchoring the outer end portion of the leafspring, the portion thereof lying between the bight of the U-shapedstamping and the anchored end portion of the leaf spring by flatwiseiiexure thereof enables vibratory motion of the armature edgewise of itslaminations.

7. In a vibratory magnetic device: an elongated movable armature; aspring mounting for one end of the armature comprising a generallyU-shaped metal stamping, Athe spaced arms of the U-shaped stamping beingextended at one side thereof to provide attaching ears overlying thesides of an end portion of the armature; fastening means securing saidattaching ears to the armature and clamping said armature therebetween,reinforcing beads in said arms of the stamping extending generallylengthwise of the armature; the

i bight of the U-shaped stamping being extended to provide a flatrelatively stiff leaf spring overlying but spaced from the portion ofthe armature which is clamped between the attaching ears of the sidearms of the stamping, the thickness of said leaf spring being a factordetermining its stiffness, and the llat disposition of the leaf springand its extension from the bight of the stamping facilitating reductionin the thickness of the leaf spring; and means on said leaf springproviding for rigidly anchoring the outer end portion thereof in amanner allowing liatwise ile'xure of the spring and consequent back andforth motion of the armature.

8. In a vibratory motor: an elongated sectional motor housing; anelectromagnet mounted in said housing section and having poles facingone side of the housing; an elongated armature; and means mounting thearmature lengthwise in said designated housing section for back andforth sidewise movement between the side of the housing and the poles ofthe electromagnet, said mounting means comprising a boss on the housingsection between one end thereof and the electromagnet, said boss havinga surface adjacent to one end of the armature and substantially normalto the direction of back and forth motion of the armature and having aslot extending through the boss substantially perpendicular to its saidsurface and opening to the top of the boss; a relatively stiff leafspring; means anchoring the leaf spring to said end of the armature withthe outer end portion of the leaf spring overlying and flatwise spacedfrom the adjacent portion of the armature, said outer end portion of theleaf spring having a hole therethrough; and a clamping screw received insaid hole and projecting from the leaf spring for ready disposition intoand removal from the slot in the boss so that mounting of the armaturein position requires merely dropping the same down into the designatedhousing section and tightening said screw to thereby clamp the outer endportion of the leaf spring to said surface of the boss.

9. In an electrical instrument of the character described: a housingcomprising complementary hollow sections, said housing sections havingregistering switch receiving pockets opening to the plane of junctionbetween the housing sections, each of said pockets having a bottom walland a substantially fiat outer wall rising from the bottom wall, atleast one of said housing sections having a hole through its saidrelatively fiat outer wall; an abutment on one of the housing sectionsspaced from the relatively fiat outer walls; and a switch for theinstrument, said switch being received in the registering pocketsbetween the bottom walls thereof and having an outer fiat face bearingagainst said fiat outer walls, and an actuator projecting from saidouter flat face and protruding through said hole, the distance betweensaid abutment and said flat walls being slightly less than the depth ofthe switch so that as the housing sections are drawn together the switchis forced between the abutment and said flat outer walls.

10. The structure set forth in claim 9 further characterized by theprovision of spaced abutments on the bottom wall of the switch receivingpocket in one of the housing sections engaging the ends of the switch tohold the same against shifting endwise.

11. In an electromagnetic clipper having a stationary blade mounted onone end of an elongated housing, a movable blade in atwise slidingengagement with the fixed blade and constrained to reciprocation acrossthe fixed blade in directions transverse to the housing axis, and amagnet coil inside the housing: an elongated rigid armature; a mountingfor said armature disposing the armature in the housing in a position tobe reciprocatingly vibrated in consequence of energization of the coilby alternating current and comprising a leaf spring having one of itsends rigidly and immovably secured to one end of the armature and havingits other end rigidly and immovably secured to a fixed part in thehousing, the blade of said leaf spring having a width substantiallygreater than its thickness and thus constraining the armature toreciprocation in directions parallel to the directions of reciprocationof said movable blade and precluding motion of the armature indirections transverse to said directions; another leaf spring having oneof its ends anchored to the other end of the armature and having itsother end anchored to the movable blade, said other leaf springproviding a connection between the armature and the movable blade whichis rigid in the directions of reciprocation of the armature and movableblade to constrain them to reciprocate in unison, but which is yieldabletransversely to said directions so that the movable blade is biased intoatwise engagement with the fixed blade; and means for adjustably varyingthe biasing force which said other leaf spring exerts upon the fixedblade, comprising a rigid bracket fixed to said other end of thearmature and projecting beyond the same to overlie said other leafspring, and a set screw in said bracket engaging said other leaf springintermediate the ends thereof.

References Cited in the file of this patent UNITED STATES PATENTS1,708,315 Lutes Apr. 9, 1929 1,810,469 Dremel June 16, 1931 1,861,043Andis May 31, 1932 2,283,551 Hanley May 19 ,1942 2,304,525 Andis Dec. 8,1942 2,396,397 Tolmie Mar. 12, 1946 2,459,412 Canham Jan. 18, 1949FOREIGN PATENTS 319,704 Italy July 18, 1934

